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So far, we've learned how to create and modify hashes and work with hash keys. Ruby provides several ways to work with the values in a hash as well. In this video, we'll explore different ways to work with the values in a hash.
Code Samples
For the examples below, we'll be working with this hash:
hash = { "item" => "Bread", "quantity" => 1, "brand" => "Treehouse Bread Company" }
To return an array of the values in the hash, we can use the values method:
hash.values
Which would return the following:
["Bread", 1, "Treehouse Bread Company"]
The has_value? method takes one argument and returns true or false if the value is contained within the hash:
hash.has_value?("brand")
That would return false since "brand" isn't a value. However, the following would return true:
hash.has_value?("Bread")
The values_at method takes several arguments and returns the hash values at the specified keys as an array:
hash.values_at("quantity", "brand")
That would return:
[1, "Treehouse Bread Company"]
Similarly, the hash keys, Ruby provides us methods for working with hash values. 0:00 Let's take a look of some of those now using WorkSpaces. 0:07 Okay, so I've just created a new ruby WorkSpace here and 0:10 here we are in the console. 0:14 Let's go ahead and launch an RIB session and start working with hash values. 0:15 So let's create a hash to work with. 0:21 The item here is gonna be bread, quantity of 1 and 0:24 the brand is still gonna be Treehouse Bread Company. 0:29 All right, so here is a hash to work with. 0:37 Now just like the method for looking at all the keys was called hash dot keys, 0:40 we have a similar method to look at all the values called values. 0:46 And that will return an array of all of the different values inside of the hash. 0:51 And again how we asked the hash if it had a key, and passed in an argument. 0:57 We can do the same thing to see if it has a value. 1:03 So we could say hash.has_value, and 1:06 then pass in a value it does not have the value brand because that's a key, but 1:09 let's see if it has a value for the number one which is the quantity and it does. 1:15 And we can also use the method value and pass in an argument. 1:25 It's pretty much the exact same thing, an alias under a different name. 1:30 If we wanted to get a couple values back from the hash, 1:36 we could use the values add method and pass in the keys that we want. 1:39 We'll say we want item and quantity and 1:45 that will return an array of the values for the keys that we passed in. 1:48 Try practicing with hashes and hash values on your own now using WorkSpaces. 1:54
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